Interpretation of characteristics of a golf swing using motion analysis

ABSTRACT

Methods, systems and apparatus for golf swing analysis are disclosed. One golf swing analysis system includes a motion sensing device attached to a golf club, the motion sensing device comprising a controller and one or more motion sensors. The golf swing analysis system further includes a remote processor, wherein a wireless link electronically connects the remote processor and the controller of the motion sensing device. Further, at least one of the controller and the remote processor are operative to access sensor data generated based on sensed signals of the one or more motion sensors, and perform pattern recognition analysis on the sensor data, comprising identifying and analyzing at least a portion of a golf swing based on the sensed data.

RELATED APPLICATIONS

This patent application claims priority to provisional patent application Ser. No. 61/879,224 filed Sep. 18, 2013, and this patent application is a continuation-in-part (CIP) of U.S. patent application Ser. No. 14/299,361, filed Jun. 9, 2014, which claims priority to provisional patent application 61/839,920, filed Jun. 27, 2013, all of which are herein incorporated by reference.

FIELD OF THE DESCRIBED EMBODIMENTS

The described embodiments relate generally to electronic sensing. More particularly, the described embodiments relate to methods, systems and apparatuses for interpretation of characteristics of a golf swing using motion analysis.

BACKGROUND

Over the past decade, the field of miniature electronics sensors has witnessed a surge of applications. This field touches a wide swath of markets and industries that are as diverse as vehicular telematics, earthquake detection, home & corporate security, senior safety, infant safety, athletic performance, sports improvement, guided missile systems, only to name a few.

One class of wireless sensors that has gained popularity in recent years is motion sensing devices. Such sensors, commonly available as accelerometers, gyroscopes, tilt sensors, shock sensors and magnetometers, have the ability to detect precise levels of acceleration, rotation and spatial orientation in three dimensions, and thereby provide a precise measure of the types of motions that occur in the objects or devices that they are attached to.

As further background, the field of golf has a large number of players who are very passionate about the sport. Golfers are perennially seeking to improve their golf swing. They take lessons from golf pros, practice drills for hours at driving ranges, and read books on golf technique.

It is desirable to have an apparatus and method for accurate interpretation of characteristics of a golf swing.

SUMMARY

An embodiment includes a golf swing analysis system. The golf swing analysis system includes a motion sensing device attached to a golf club, the motion sensing device comprising a controller and one or more motion sensors. The golf swing analysis system further includes a remote processor, wherein a wireless link electronically connects the remote processor and the controller of the motion sensing device. Further, at least one of the controller and the remote processor are operative to access sensor data generated based on sensed signals of the one or more motion sensors, and perform pattern recognition analysis on the sensor data, comprising identifying and analyzing at least a portion of a golf swing based on the sensed data.

Another embodiment includes a method of analyzing a golf swing. The method includes sensing motion, by a motion sensing device attached to a golf club, the motion sensing device comprising a controller and one or more motion sensors, accessing, by a controller, sensor data generated based on sensed signals of the one or more motion sensors, performing pattern recognition analysis on the sensor data, comprising identifying and analyzing at least a portion of a golf swing based on the sensed data, wherein the at least one portion of the golf swing includes at least one of an address portion, a takeaway portion, a first-half of back swing portion, a top of back swing portion, down swing portion, an impact portion, and a follow through portion.

Other aspects and advantages of the described embodiments will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, illustrating by way of example the principles of the described embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a golf club motion sensor, according to an embodiment.

FIG. 2 shows golf body motion sensors, according to an embodiment.

FIG. 3 shows reference directions of a golf club, according to an embodiment.

FIG. 4 shows reference angular orientations of a golf club, according to an embodiment.

FIG. 5 shows a display that depicts a determination of a lie angle, according to an embodiment.

FIG. 6 is a flow chart that includes steps of a method of determining the lie angle of a golf club when a golfer is taking a swing, according to an embodiment.

FIG. 7 shows a display that depicts a determination the takeaway direction of the golf club when a golfer is taking a swing, according to an embodiment.

FIG. 8 is a flow chart that includes steps of a method of determining the takeaway direction of the golf club when the golfer is taking a swing, according to an embodiment.

FIG. 9 shows a display that depicts a determination the backswing plane orientation of the golf club, when the golfer is taking a swing, according to an embodiment.

FIG. 10 is a flow chart that includes a method of determining the backswing plane of the golf club when the golfer is taking a swing, according to an embodiment.

FIG. 11 shows a display that depicts a determination the downswing plane orientation of the golf club, when the golfer is taking a swing, according to an embodiment.

FIG. 12 is a flow chart that includes steps of a method of downswing plane orientation of the golf club when the golfer is taking a swing.

FIG. 13 shows a display that depicts a determination of the backswing length of the golf club, when the golfer is taking a swing, according to an embodiment.

FIG. 14 is a flow chart that includes steps of a method of determining the backswing length of the golf club, when the golfer is taking a swing, according to an embodiment.

FIG. 15 shows a display that depicts a determination of the release timing of the golf club, when the golfer is taking a swing, according to an embodiment.

FIG. 16 is a flow chart that includes steps of a method of determining the release timing of the golf club, when the golfer is taking a swing, according to an embodiment.

FIG. 17 shows a display that depicts a determination of timing of the top speed of the golf club, when the golfer is taking a swing, according to an embodiment.

FIG. 18 is a flow chart that includes steps of a method of determining the timing of the top speed of the golf club, when the golfer is taking a swing, according to an embodiment.

FIG. 19 shows a display that depicts a determination of the downswing acceleration of the golf club when the golfer is taking a swing, according to an embodiment.

FIG. 20 is a flow chart of a method of determining the downswing acceleration of the golf club when the golfer is taking a swing, according to an embodiment.

FIG. 21 shows a display that depicts a determination of the downswing arc of the golf club, when the golfer is taking a swing, according to an embodiment.

FIG. 22 is a flow chart that includes steps of a method of determining the downswing arc of the golf club, when the golfer is taking a swing, according to an embodiment.

FIG. 23 is a flow chart that includes steps of a method of determining the degree of rotation of the golf club when the golfer is taking a swing, according to an embodiment.

FIG. 24 shows a block diagram of a golf club (motion) sensor, according to an embodiment.

DETAILED DESCRIPTION

The described embodiments are related to the technological field of motion detection, capture and pattern recognition using electronic sensors, and to the plotting, analysis and interpretation of the characteristics of golf movements, that may be either human movements or equipment movements or a combination thereof. The described embodiments further relate to an electronic and electro-mechanical apparatus that can precisely trace and record a three-dimensional trajectory of a golf swing, and a method to plot, analyze and interpret the various attributes of the golf swing.

The described embodiments further include methods to analyze and interpret the various types of golf swings that are taken by a golfer, in the same manner that a golf instructor would. These golf swings are comprised of a combination of the motion of a golf club and the motion of the golfer wielding the club. Enabled by miniature motion sensors attached to the golf club or to the golfer's body, the described embodiment include analysis of the recorded trajectory of the golf motion using signal processing and pattern recognition, and outputs meaningful characteristics and attributes of the golf swing to the golfer. These characteristics and attributes are a close approximation of those that would be determined by a skilled golf instructor observing the golfer's swing.

Golfers, as a group, have a great deal of passion for the game. They love to practice and they love even more to compete. In order to improve, they read books on golf techniques, watch videos and even may take lessons from a golf pro once in a while.

However, during practice, it is simply not practical to have a golf instructor watching, and analyzing every swing they take. Also, it is not practical to film one's own swing with high speed video cameras from several angles on a constant basis. As a result, golfers really have no good idea of whether they are making the necessary corrections in their swing to improve their game.

Furthermore, only around 10% of the population of golfers takes golf lessons. That means that the vast majority of them do not have good knowledge of the characteristics of their swing. In most cases golfer do know the outcome of each swing, such as a slice, hook, fade, draw, shank or topping the ball. They are also likely to know if they have a tendency to slice, hook or top, or simply spray it all over from one shot to the next. However, there can be several causes for a slice or a hook, and in most cases they relate to the shape of the swing, and the golfer's body movements. Most golfers, especially those who rarely take lessons, do not have a good idea of what aspects of their swing shape or body movements cause the poor shot.

The described embodiments address the problem articulated above in a novel and innovative way, using electronic and electro-mechanical motion sensors, combined with a unique method for interpreting the trajectory of the golf club or golfer's body movements.

One benefit of the described embodiments is to provide golfers with a qualitative “instructor-like” feedback on their golf swing from the application, while taking golf swings in any convenient environment, such as in their backyards, basements or garages (hitting into a net), at a driving range or on a real golf course. They can use the same golf clubs they use for their regular game, not simulators or contrivances. Utilizing the described embodiments, golfers learn the attributes and flaws in their golf swing, and with that knowledge are able to focus on their deficiencies and improve their golf game.

A golf swing includes a golf club with which the ball is struck, and a human being who moves his or her body in order to strike the ball.

At least some of the described embodiments include two categories of apparatuses. The first is a golf club motion sensor that is able to capture the movements of the golf club accurately and with precision. The second is a group of golfer body motion sensors that are able to capture the movements of the golfer's body accurately and with precision.

FIG. 1 shows a golf club motion sensor 100 according to an embodiment. The golf club motion sensor 100 is an electronic device that includes of motion sensors that can precisely measure linear acceleration, angular velocity and acceleration and device orientation. For an embodiment, the golf club sensor 100 attaches securely to a golf club by way of a clamping mechanism. When a golfer takes a golf swing, the golf club motion sensor 100 registers the parameters of the motion and conveys them wirelessly to a computing device. The golf club motion sensor 100 is also capable of wirelessly receiving additional motion data from subordinate or ancillary sensor devices and transferring the combined set of motion parameters to the computing device.

Important characteristics of the golf club sensor 100 include the golf club sensor being miniature and lightweight, and having a negligible impact on the weight of the golf club, virtually too small to notice for the golfer. Further, an embodiment of the golf club sensor is tethered to an appropriate position on the golf club, where it is able to detect the linear and angular motion of the golf club. Further, an embodiment of the golf club sensor includes high precision electronic and/or electro-mechanical components that are able to detect linear acceleration of the sensor in three dimensions. Further, an embodiment of the golf club sensor includes high precision electronic and/or electro-mechanical components that are able to detect angular (rotational) acceleration of the sensor in three dimensions. Further, an embodiment of the golf club sensor includes a wireless transmission mechanism that is able to transmit data collected by the sensor to a proximal or remote data collection device. Further, an embodiment of the golf club sensor includes an electronic storage capability, to collect and store data within itself, until such future time that the data can be suitably transferred, wirelessly or via an electrical cable, to a proximal or remote data collection device.

FIG. 2 shows golf body motion sensors 210, 220, 230 according to an embodiment. For at least some embodiments, the golf body motion sensors 210, 220, 230 are capable of sending motion data to the golf club motion sensor 100, which can then transport the combined set of motion data to a computing device. Golf body motion sensor 210 includes a glove that contains a wireless motion sensor, capable of transporting data related to the movement of the wrist. Golf body motion sensor 220 includes a golf cap that contains a wireless motion sensor, capable of transporting data related to the movement of the head. Golf body motion sensor 220 includes a vest or shirt that contains one or more wireless motion sensors, capable of transporting data related to the movement of the torso.

For at least some embodiments, desirable positions of the golf body motion sensors are at the neck, shoulders, waist, wrist, head, forearms, upper arms, thighs, lower legs and feet, or any combination thereof. The golf body motion sensors may to be placed at one, multiple, or every single position identified above, and typically would be placed selectively at only those positions that provide the optimal information about the golfer's swing. For at least some embodiments, each body sensor is miniature and lightweight, virtually too small to notice for the golfer. For at least some embodiments, each sensor is tethered to an appropriate position on the golfer's body via an appropriate body harness, which can be either (a) a strap that is elastic, Velcro, buttoned or zippered, (b) a suspender, apparel or under-clothing worn by the golfer, cap, glove, sock, shoe, it is able to detect the linear and angular motion of the golf club. For at least some embodiments, each sensor contains high precision electronic and/or electro-mechanical components that are able to detect linear acceleration of the sensor in three dimensions. For at least some embodiments, each sensor contains high precision electronic and/or electro-mechanical components that are able to detect angular (rotational) acceleration of the sensor in three dimensions. For at least some embodiments, each sensor contains a wireless transmission mechanism that is able to transmit data collected by the sensor to a proximal or remote data collection device. For at least some embodiments, each sensor contains an electronic storage capability, to collect and store data within itself, until such future time that the data can be suitably transferred, wirelessly or via an electrical cable, to a proximal or remote data collection device.

Golf Swine Motion Analysis

For at least some embodiments, the motion sensors that are tethered to the golf club or worn on the human body have the ability to capture the motion of the golf club or of various locations on the human body. This motion can be classified as (a) linear acceleration and displacement, in one of three dimensions, (b) angular velocity and displacement, in one of three dimensions, (c) Orientation of the sensor, based on the force of gravity, and/or based on the direction indicated by a compass.

At the start of a motion capture sequence, a reference position is established as a baseline. Deviations of the sensor from this reference position is determined with high precision, represented as angular and linear displacements as a function of time. The sensor readings are sampled at a very high rate, resulting in the ability to plot the location and orientation of the sensor in three dimensions with very high precision, as a function of time. By using spherical trigonometry, and equipped with the knowledge of the mounting position(s) of the sensor(s) on the golf club or human body, a highly accurate plot of the trajectory and orientation of the golf club is mapped out in three dimensions.

In order to provide context to the linear and angular orientations, the following nomenclature is adopted for the linear axes and the axes of rotation of the golf club.

FIG. 3 shows reference directions of a golf club, according to an embodiment. The reference directions of FIG. 3 are defined and referenced by the described embodiments. For an embodiment, the X-axis is along the direction of the golf club shaft, and the Y-axis is perpendicular to the direction of the club head and also perpendicular to the direction of the golf club shaft. The Z-axis is along the direction of the club head and perpendicular to the direction of the golf club shaft.

FIG. 4 shows reference angular orientations of a golf club, according to an embodiment. The reference angular orientations of FIG. 4 are defined and referenced by the described embodiments. For an embodiment, the α-axis of rotation is along the direction of the golf club shaft, the β-axis of rotation is perpendicular to the direction of the club head and also perpendicular to the direction of the golf club shaft, and the γ-axis of rotation is along the direction of the club head and perpendicular to the direction of the golf club shaft.

Interpretation of Swings

Based on the type of motions, various types of swings can be interpreted. FIG. 5 shows a display that depicts a determination of a lie angle, according to an embodiment. For at least some embodiments, determine when the golfer is taking a swing whether the lie angle is optimal, too shallow or too vertical.

Lie Angle

The lie angle is the direction made by the club with the ground, at the time of address as well as the time of ball impact. The accelerometers within the sensor provide a precise indication of the orientation of the golf club at the time that the golfer is addressing the ball. From the time that golf swing commences to the time that the ball is struck, the deviation in lie angle is computed and presented by the application. The described embodiments include a determination of whether the lie angle is: (i) Too shallow, (ii) Optimal, or (iii) Too high.

FIG. 6 is a flow chart that includes steps of a method of determining the lie angle of a golf club when a golfer is taking a swing, according to an embodiment.

Step 601 includes capturing accelerometer and gyroscope data that is captured by the golf club sensor 100. This data is continually measured. In step 602 the system awaits a condition where there is no movement in the data for over one second, and when this condition arises, the method transitions to step 604. In step 604, the accelerometer data in item 603 is collected, which facilitates the computation of the direction of gravity in step 604. Once the direction of gravity is known, in step 605 the angle between the X-axis and the gravity vector (direction of gravity) is computed. From this, the Lie Angle can be determined directly and published. That is, an embodiment includes analyzing an address portion of the golf swing including processing the sensor data to determine whether a lie angle is too shallow, optimal, or too high. For an embodiment, determining the lie angle includes sensing an x-axis along a shaft of the golf club, sensing a gravity vector, and computing an angle between the x-axis and the gravity vector.

Takeaway Direction

FIG. 7 shows a display that depicts a determination the takeaway direction of the golf club when a golfer is taking a swing, according to an embodiment. For at least some embodiments, the determination the takeaway direction of the golf club indicates when the golfer is taking a swing and judge whether it is straight, “inward” or “outward”.

One of the most important assessments for the golfer is the direction of takeaway of the club from the address position. For a good golf stroke, it is important for the club to be moved straight backward. However, in some cases, the golfer may move the club backward and inward, and in other cases the club may be moved backward and outward. Both of these are flaws that may negatively affect the way in which the ball is struck. The described embodiments include a determination of whether the takeaway direction is: (i) outward, (ii) straight back, and (iii) inward.

FIG. 8 is a flow chart that includes steps of a method of determining the takeaway direction of the golf club when the golfer is taking a swing, according to an embodiment. Step 801 includes continually collecting data from the sensor as shown in item 802. This data is continually measured. In step 803 the system awaits a condition where there is no movement in the data for over one second, and when this condition arises, it transitions to step 805. In step 805, the accelerometer and gyroscope data in item 804 is collected. In step 805, the data is evaluated for positive motion of Z axis and β-axis rotation. If so, then the Takeaway Direction is published as “Outward” in step 806. Else, in step 807, the data is evaluated for negative motion of Z axis and β-axis rotation. If so, then the Takeaway Direction is published as “Inward” in step 808. Else, in step 809, the data is evaluated for neutral motion of Z axis and β-axis motion. If so, then the Takeaway Direction is published as “Straight” in step 810.

For an embodiment, determining the takeaway direction of the golf swing includes sensing accelerometer data and gyroscope data of the sensor data during the takeaway portion, wherein the accelerometer data includes Z-axis motion, wherein the Z-axis motion is perpendicular to a shaft of the golf club and planar to grooves of the golf club, and wherein the gyroscope data includes rotational (β-axis) movement of the golf club that is perpendicular to a shaft of the golf club and planar to grooves of the golf club, and determining the takeaway direction by identifying negative or positive directions of the Z-axis motion and negative or positive rotational (β-axis) movement of the golf club.

Backswing Plane

FIG. 9 shows a display that depicts a determination the backswing plane orientation of the golf club, when the golfer is taking a swing, according to an embodiment. For at least some embodiments, the determination the backswing plane orientation of the golf club, when the golfer is taking a swing indicates whether the backswing plane is optimal, too horizontal or too vertical.

The backswing plane is another swing characteristic that can affect how the ball is struck. Swings that are too vertical may cause a pull slice or erratic stroking of the ball, whereas swings that are too horizontal (flat) may cause a push hook. An optimal backswing plane sets the golfer up for an optimal downswing plane. At least some of the described embodiment includes a determination of whether the backswing plane is: (i) vertical, (ii) optimal, and (iii) flat or horizontal.

FIG. 10 is a flow chart that includes a method of determining the backswing plane of the golf club when the golfer is taking a swing, according to an embodiment. Starting at step 1010, at least some embodiments include continually collecting data from the sensor as shown in item 1011. This data is continually measured. In step 1012 a condition is awaited where there is no movement in the data for over one second (or some predetermined threshold of time), and when this condition arises, the method transitions to step 1014. In step 1014, a 3-dimensional arc of the backswing is computed. In step 1015 a computation of the closest match plane for the backswing arc is performed. In step 1016 a computation of the angle between the backswing plane and the gravity vector is performed. In step 1017 this angle is matched with pre-determined thresholds for flat, vertical and normal backswing plane angles and a determination of “optimal”, “too horizontal” or “too vertical” is made. Finally, in step 1018 based on the match with the thresholds, the finding regarding the nature of the backswing plane is published.

For an embodiment, analyzing the backswing portion of the golf swing includes processing the sensor data to determine whether a backswing plane is vertical, optimal, or flat, wherein analyzing the first-half of the back swing comprises continuously collecting the sensor data, identifying a condition of no movement for greater than a threshold of time, computing a backplane plane that is a closest match plane for a backswing arc, computing an angle between the backswing plane and a gravity vector of the sensor data, and comparing the angle with a predetermined set of threshold, wherein the threshold identify the backswing plane as vertical, optimal, or flat.

Downswing Plane

FIG. 11 shows a display that depicts a determination the downswing plane orientation of the golf club, when the golfer is taking a swing, according to an embodiment. For at least some embodiments, the determination the downswing plane orientation of the golf club, when the golfer is taking a swing indicates whether the downswing is is optimal, too horizontal or too vertical.

Like the backswing plane, the downswing plane is another swing characteristic that can affect how the ball is struck. Often, the backswing and downswing planes are different, because the golfer has a loop at the top of the swing. Downswings that are too vertical may cause a pull slice or erratic stroking of the ball, whereas downswings that are too horizontal (flat) may cause a push hook. An optimal backswing plane sets the golfer up for an optimal downswing plane. At least some of the described embodiments include a determination of whether the downswing plane is: (i) vertical, (ii) optimal, and (iii) flat or horizontal.

FIG. 12 is a flow chart that includes steps of a method of downswing plane orientation of the golf club when the golfer is taking a swing. Starting at step 1210, data from the sensor is continually collected as shown in item 1211. This data is continually measured. In step 1212 a condition is awaited where the club is ascertained to be at the top of the backswing, based on a momentary pause and the transition of Y-axis angular rotation from negative to positive. When the Y-axis angular rotation from negative transitions to positive, the method transitions to step 1214, which includes continually collecting data from item 1213. Step 1214, the platform computes the 3-dimensional arc of the downswing. In step 1215 includes performing a computation of the closest match plane for the downswing arc. Step 1216 includes performing a computation of the angle between the downswing plane and the gravity vector. Step 1217 includes taking this angle and matching it with pre-determined thresholds for flat, vertical and normal downswing plane angles and making a determination of “optimal”, “too horizontal” or “too vertical”. Finally, step 1218 includes publishing the finding regarding the nature of the downswing plane based on the match with the thresholds.

An embodiment includes analyzing the downswing portion including processing the sensor data to determine whether a downswing plane is vertical, optimal, or flat. For an embodiment, determining whether a downswing plane is vertical, optimal, or flat includes ascertaining that the golf swing is at a top of a back swing of the golf swing, comprising identifying a momentary pause and a transition of a Y-axis angular rotation from negative to positive, wherein the Y-axis is perpendicular to shaft of the golf club and perpendicular to grooves of the golf club, computing a three-dimensional arc of the downswing, identifying a downswing plane by computing a closest match plane of the three-dimensional arc of the downswing, computing an angle between the downswing plane and a gravity vector, and comparing the angle with a predetermined set of threshold, wherein the threshold identify the backswing plane as vertical, optimal, or flat.

Backswing Length

FIG. 13 shows a display that depicts a determination of the backswing length of the golf club, when the golfer is taking a swing, according to an embodiment. The backswing length is an important determinant in the golfer generating the optimal amount of power at impact. Backswings that are too short do not leave enough traversal distance for the golfer to generate the proper speed. Backswing that are too long (over-rotated) may lead to too much traversal of the club head, which in turn will result in good power but erratic striking of the ball. At least some of the described embodiments include a determination of whether the backswing length is: (i) too long, (ii) too short or (iii) optimal, or parallel to ground at top of backswing.

FIG. 14 is a flow chart that includes steps of a method of determining the backswing length of the golf club, when the golfer is taking a swing, according to an embodiment. Starting at step 1410, the method includes continually collecting data from the sensor as shown in item 1411. This data is continually measured. Step 1412 includes awaiting a condition where there is no movement in the data for over one second (or some time selected threshold), and when this condition arises, the method transitions to step 1414. Step 1414 includes computing the 3-dimensional arc of the backswing. Step 1415 includes evaluating whether the golf club is at the top of the backswing or not. If the golf club is at the top of the backswing, the method transitions to step 1416, where the angle between the X-axis and the ground plane is computed. In step 1417 an evaluation is made of whether the angle in step 1416 is in the zone for “Short backswing”, and if so the platform publishes “Backswing too short” in step 1418. Else, in step 1419 an evaluation is made of whether the angle in step 1416 is in the zone for “Long backswing”, and if so the platform publishes “Backswing too long” in step 1420. Else, in step 1421 an evaluation is made of whether the angle in step 1416 is in the zone for “Optimal backswing”, and if so the platform publishes “Optimal backswing length” in step 1422.

Release Timing

FIG. 15 shows a display that depicts a determination of the release timing of the golf club, when the golfer is taking a swing, according to an embodiment. The release timing is one of the most important considerations for achieving optimal power. A “release” occurs on the downswing when the wrist is uncocked. For optimal power, the wrist should remain cocked as long as possible, and should be uncocked in a whip-like movement right before the ball is struck. If the wrist is uncocked too early, it will usually lead to loss of power. Likewise, if the wrist is uncocked without the whip-like movement, it will lead to a loss of power. Finally, if the wrist is uncocked too late, the club will still be accelerating at the time that the ball is struck and there will be a loss of power. At least some of the described embodiments include a determination of whether the golf swing includes: (i) early release, (ii) optimal release, and (iii) late release.

FIG. 16 is a flow chart that includes steps of a method of determining the release timing of the golf club, when the golfer is taking a swing, according to an embodiment. Starting at step 1610, the method includes continually collecting data from the sensor as shown in item 1611. This data is continually measured. Step 1612 includes awaiting a condition where the club is ascertained to be at the top of the backswing, based on a momentary pause and the transition of Y-axis angular rotation from negative to positive. When this condition arises, the method transitions to step 1614, and further includes continually collecting data from item 1613. Step 1614 includes evaluating whether a double pendulum motion, as indicated by the γ-axis has commenced. If so, in step 1615 the angle between the X-axis and the ground plane is computed. In step 1616 an evaluation is made of whether the angle in step 1615 is in the zone for “early release”, and if so the platform publishes “Early release” in step 1617. Else, in step 1618 an evaluation is made of whether the angle in step 1615 is in the zone for “Optimal release”, and if so the platform publishes “Optimal release” in step 1619. Else, in step 1620 an evaluation is made of whether the angle in step 1621 is in the zone for “Late release”, and if so the platform publishes “Late release” in step 1621.

For at least some embodiment, processing the sensor data to determine whether a release time is too early, optimal, or too late, wherein determining whether the release time is too early, optimal, or too late includes, continuously collecting the sensor data, ascertaining the golf club to be at a top of a backswing by identifying a momentary pause of the golf club and identifying a transition of a Y-axis angular rotation from negative to positive, wherein the Y-axis is perpendicular to shaft of the golf club and perpendicular to grooves of the golf club, identifying a double pendulum motion based on a sensed γ-axis angular rotation, wherein the γ-axis angular rotation is perpendicular to shaft of the golf club and parallel to grooves of the golf club, determining an angle between and X-axis of motion and a ground plane, wherein the X-axis is along a shaft of the golf club, and based on the determined angle, identify whether the release time is too early, optimal, or too late.

Timing of Top Speed

FIG. 17 shows a display that depicts a determination of timing of the top speed of the golf club, when the golfer is taking a swing, according to an embodiment. As with the release timing, the timing of top speed of the club is extremely important for achieving the maximum distance. A good golfer will achieve the top speed at the precise instant that the ball is struck. A lesser golfer may achieve top speed either before impact or after impact. Neither of these conditions is good. At least some of the described embodiments include a determination of whether (i) The top club speed is reached before impact, (ii) The top club speed is reached at impact, or (iii) The top club speed is reached after impact.

FIG. 18 is a flow chart that includes steps of a method of determining the timing of the top speed of the golf club, when the golfer is taking a swing, according to an embodiment. Starting at step 1810, the method includes continually collecting data from the sensor as shown in item 1811. This data is continually measured. Step 1812 includes awaiting a condition where the club is ascertained to be at the top of the backswing, based on a momentary pause and the transition of Y-axis angular rotation from negative to positive. When this condition arises, the method transitions to step 1814, and further includes continually collecting data from item 1813. In step 1814 the platform waits for a characteristic signature pattern to indicate impact between the club and the golf ball. Once this happens, in step 1815 an evaluation is made of whether the γ-axis angular speed is faster than the prior sample, and if so the “Top speed after impact” are published in step 1816. Else, in step 1817 an evaluation is made of whether the γ-axis angular speed is equal to the prior sample, and if so the “Top speed at impact” is published in step 1818. Else, in step 1819 an evaluation is made of whether the γ-axis angular speed is slower to the prior sample, and if so the “Top speed before impact” are published in step 1820.

At least some embodiments include determining whether a timing of top speed of the golf swing is reach before impact, at impact or after impact with a golf ball, wherein determining whether a timing of top speed of the golf swing is reach before impact, at impact or after impact with a golf ball includes continuously collecting the sensor data, ascertaining the golf club to be at a top of a backswing by identifying a momentary pause of the golf club and identifying a transition of a Y-axis angular rotation from negative to positive, wherein the Y-axis is perpendicular to shaft of the golf club and perpendicular to grooves of the golf club, identifying a characteristic motion signature pattern to indicate impact between the golf club and a golf ball, after identifying the characteristic motion signature pattern to indicate impact between the golf club and a golf ball, determining whether a sample of an γ-axis angular speed of the sensor data is faster, equal or slower than a prior sample of the γ-axis angular speed of the sensor data, wherein the γ-axis angular speed is perpendicular to shaft of the golf club and parallel to grooves of the golf club, and determining whether the timing of top speed of the golf swing is reach before impact, at impact or after impact with the golf ball based on whether sample of the γ-axis angular speed of the sensor data is faster, equal or slower than the prior sample of the γ-axis angular speed of the sensor data.

Downswing Acceleration Timing

FIG. 19 shows a display that depicts a determination of the downswing acceleration of the golf club when the golfer is taking a swing, according to an embodiment. It is important for the golfer to have a smooth acceleration on the downswing that builds up to maximum speed at the time that the ball is struck. Lesser golfers will rush their downswing, thereby expending their power at the top of the downswing, instead of a constant build-up of speed. At least some of the described embodiments include a determination of whether (i) the golfer has smooth, constant acceleration, (ii) early acceleration, of (iii) late acceleration.

FIG. 20 is a flow chart of a method of determining the downswing acceleration of the golf club when the golfer is taking a swing, according to an embodiment. Starting at step 2010, the method includes continually collecting data from the sensor as shown in step 2011. This data is continually measured. Step 2012 includes awaiting a condition where the club is ascertained to be at the top of the backswing, based on a momentary pause and the transition of Y-axis angular rotation from negative to positive. When this condition arises, the method transitions to step 2014, and further includes continually collecting data from item 2013. In step 2014 the platform records the Y-axis angular acceleration and X-axis linear acceleration in the early stage of the downswing. In step 2015 the platform records the Y-axis angular acceleration and X-axis linear acceleration in the late stage of the downswing. In step 2016, if the early acceleration computed in step 2014 exceeds the late acceleration in step 2015 than the platform publishes “Early downswing acceleration” in step 2017. Else, in step 2018, if the early acceleration computed in step 2014 equals the late acceleration in step 2015 than the platform publishes “Smooth downswing acceleration” in step 2019. Else, in step 2020, if the early acceleration computed in step 2014 is less than the late acceleration in step 2015 than the platform publishes “Late downswing acceleration” in step 2021.

At least some embodiments include determining whether the downswing acceleration is constant, early or late, wherein determining whether the downswing acceleration is constant, early or late includes continuously collecting the sensor data, ascertaining the golf club to be at a top of a backswing by identifying a momentary pause of the golf club and identifying a transition of a Y-axis angular rotation from negative to positive, wherein the Y-axis is perpendicular to shaft of the golf club and perpendicular to grooves of the golf club, collecting Y-axis angular acceleration and X-axis linear acceleration in the early stage of the downswing, wherein the y-axis angular acceleration is perpendicular to shaft of the golf club and perpendicular to grooves of the golf club and the X-axis linear acceleration is parallel to a shaft of the golf club, collecting Y-axis angular acceleration and X-axis linear acceleration in the late stage of the downswing, and determining the downswing acceleration to be constant, early or late based on whether the Y-axis angular acceleration and X-axis linear acceleration in the early stage of the downswing exceed, is equal to, or less than the Y-axis angular acceleration and X-axis linear acceleration in the late stage of the downswing.

Downswing Arc

FIG. 21 shows a display that depicts a determination of the downswing arc of the golf club, when the golfer is taking a swing, according to an embodiment. When the golfer is taking a swing at least some of the described embodiments include judging whether the downswing arc matches the backswing, is narrower than the backswing or is wider than the backswing. For optimal stroke-making, it is important for the downswing arc to be “inside” the backswing arc, mainly due to the fact that the golfer's hips and torso are naturally moving from back foot to front foot as the ball is struck. Lesser golfers may have a tendency to hit off the back foot. At least some of the described embodiments include a determination of whether the arc of the downswing relative to the arc of the backswing.

FIG. 22 is a flow chart that includes steps of a method of determining the downswing arc of the golf club, when the golfer is taking a swing, according to an embodiment. Starting at step 2210, the method includes continually collecting data from the sensor as shown in item 2211. This data is continually measured. Step 2212 includes awaiting a condition where the club is ascertained to be at the top of the backswing, based on a momentary pause and the transition of Y-axis angular rotation from negative to positive. When this condition arises, the method transitions to step 2214, and further includes continually collecting data from item 2213. In step 2214 the method includes using the data samples from the linear axes and the angular rotation axes to plot the backswing and downswing in 3-dimensional space. Then, in step 2215 the method includes recording the relative positions of the downswing and backswing arcs. In step 2216, if the backswing arc computed in step 2215 is inside the downswing arc, then the method includes publishes “Downswing arc inside backswing” in step 2217. Else, in step 2218 if the backswing arc computed in step 2215 is the same as the downswing arc, then the method includes publishes “Downswing arc same as backswing” in step 2218. Else, in step 2219 if the backswing arc computed in step 2215 is outside the downswing arc, then the platform publishes “Downswing arc outside backswing” in step 2220.

At least some embodiments include determining the downswing arc relative to the backswing arc includes continuously collecting the sensor data, ascertaining the golf club to be at a top of a backswing by identifying a momentary pause of the golf club and identifying a transition of a Y-axis angular rotation from negative to positive, wherein the Y-axis is perpendicular to shaft of the golf club and perpendicular to grooves of the golf club, using sensor data samples from the linear axes and the angular rotation axes to plot the backswing and downswing in 3-dimensional space, recording relative positions of the downswing arc and backswing arc, and identifying the downswing arc relative to the backswing arc as inside, same, or outside based on the relative positions of the downswing arc and backswing arc.

Wrist Rotation at Halfway Point of Backswing/Wrist Rotation at Top of Backswing

The wrist rotation of the golfer is an extremely important consideration in determining how the ball will be struck. At the 9 o'clock position on the backswing, the clubhead should optimally be pointing straight upward, whereas at the top of the backswing, it should ideally be pointing downward. Golfers whose club orientations are sub-optimal are likely to hit a slice or hook. At least some of the described embodiments include a determination of whether the orientation of the clubhead can be determined with high precision as the club traverses through the backswing and downswing.

FIG. 23 is a flow chart that includes steps of a method of determining the degree of rotation of the golf club when the golfer is taking a swing, according to an embodiment. Starting at step 2310, the method includes continually collecting data from the sensor as shown in item 2311. This data is continually measured. Step 2312 include awaiting a condition where the club is ascertained to be motionless, based on a momentary pause exceeding one second. When this condition arises, it transitions to step 2314, continually collecting data from item 2313. In step 2314 the method includes waiting for the condition where the Y-axis is moving in the negative direction combined with the γ-axis angular motion commencing, which signals the start of the backswing. Once this condition occurs, in step 2315 the method includes waiting for the condition where the γ-axis has rotated 90 degrees. Once that is ascertained, in step 2316 the angle between the Z-axis and the ground plane is computed as well as the rotation of the α-axis. In step 2317 the method includes determining whether the angle computed in step 2316 is less than 90 degrees, and if so, the method includes publishes “Under-rotation of club” in step 2318. Else, in step 2319 if the angle computed in step 2316 is approximately equal to 90 degrees, it publishes “Optimal club rotation” in step 2320. Else, in step 2321 if the angle computed in step 2316 is greater than 90 degrees, it publishes “Over rotation of club” in step 2322.

At least some embodiments include determining an orientation of the golf club as the golf club traverses through a backswing and a downswing including continuously collecting the sensor data, identifying a condition of no movement for greater than a threshold of time, identifying a condition in which an Y-axis is moving in the negative direction combined with an γ-axis angular motion commencing, thereby indicating a start of the backswing, wherein the Y-axis is perpendicular to shaft of the golf club and perpendicular to grooves of the golf club and the γ-axis angular motion is perpendicular to shaft of the golf club and parallel to grooves of the golf club, after start of the backswing, identifying a condition in which a γ-axis rotates 90 degrees, after the condition in which a γ-axis rotates 90 degrees, computing an angle between a Z-axis and a ground plane, wherein the Z-axis is perpendicular to shaft of the golf club and planar to grooves of the golf club, compute rotation in an α-axis, wherein the α-axis is planar to the shaft of the golf club, determining the orientation of the golf club as the golf club traverses through a backswing and a downswing as under-rotation of the golf club, optimal rotation of the golf club, over-rotation of the golf club based on whether the angle is less than 90 degrees, approximately equal to 90 degrees, or greater than 90 degrees.

FIG. 24 shows a block diagram of a golf club (motion) sensor 2400, according to an embodiment. The motion sensor 2400 includes a controller 2430, and motion sensing electronics 2420. At least some embodiments further includes I/O (input/output) electronics that allows the controller 2430 to electrically interface with an external controller 2450. Further, at least some embodiments include a mechanical switch 2410 which can be included to conserve power when the golf club sensor 2400 is inactive.

For an embodiment, the motion sensor 2400 in conjunction with the external controller 2450 forms a golf swing analysis system. For an embodiment, the golf swing analysis system includes the motion sensing device (motion sensor 2400) attached to a golf club, wherein the motion sensing device includes the controller 2430 and one or more motion sensors of the motion sensing electronics 2420. Further, the golf swing analysis system includes the remote processor (external controller 2450), wherein a wireless link electronically connects the remote processor 2450 and the controller 2430 of the motion sensing device 2400. Further, at least one of the controller 2430 and the remote processor 2450 (that is, the controller 2430 may perform the operations, the remote processor 2450 may perform the operations, or the controller 2430 and the remote processor 2450 may perform the operations in conjunction) are operative to access sensor data generated based on sensed signals of the one or more motion sensors, perform pattern recognition analysis on the sensor data, comprising identifying and analyzing at least a portion of a golf swing based on the sensed data.

For at least some embodiments, at least one of the controller and the remote processor are further operative to perform the identifying and analyzing of the at least a portion of a golf swing based sensed linear axis rotation and sensed angular axis of rotation of the golf club as shown in FIG. 3 and FIG. 4. Further, for at least some embodiments, the sensed linear axis of rotation includes three degrees of freedom and the sensed angular axis of rotation includes three degrees of freedom.

For at least some embodiments, the pattern recognition analysis includes conditional processing, wherein conditions of the processing are dependent upon sensing motion thresholds. For at least some embodiments, the pattern recognition that is employed by the system uses specific algorithms that rely on a decision tree structure for resolution and interpretation of the motion. These algorithms commence with a common baseline in each case that is the reference position of the motion sensing device. From that reference position, the motion sensing device can traverse a very large set of paths and angular deviations at varying rates, which collectively comprise the golf swing. This collective set of swing motion paths and rates represent the various permutations that characterize the swing type. Taken in totality, this number of permutations is too large to process effectively. However, a decision tree methodology with conditional processing at each mini-traversal of the golf club allows the swing to be interpreted and characterized—they form the basis of the pattern recognition, and allow the analysis to be simplified. At each mini-traversal of the golf club, the system determines the motion parameters at that point, and slots them into select ranges or threshold crossings. From that point, the next mini-traversal takes the club to a new position where new ranges and threshold crossings will apply. In this manner, once all the mini-traversals are completed, the complete interpretation of the swing is made possible.

For at least some embodiments, the motion thresholds include at least one of linear axis of rotation motion thresholds and angular axis of rotation motion thresholds. As described, the motion sensing device contains sensors that provide linear acceleration, angular velocity and angular acceleration data in conjunction with the rate of traversal. The values assumed by the linear and angular motion parameters can be classified into a set of ranges to facilitate interpretation of the motion. The boundary of each range is the threshold that determines whether a measurement falls within a given range or in the adjacent one.

For at least some embodiments, the at least one portion of the golf swing is identified based on a temporal component, a displacement component and an acceleration component. The motion sensing device, during the traversal through the swing, follows a trajectory in space. This trajectory can be decomposed into a sequence of mini traversals. Each mini traversal may be considered to be an element of the vocabulary of possible swing motions at that point. These mini traversals are identified by time, space, angular deviation and rate of motion. Time is characterized as a temporal component, space is characterized as a displacement component, and the rate of traversal through space is characterized as an acceleration component.

For at least some embodiments, the at least one portion of the golf swing includes at least one of an address portion, a takeaway portion, a first-half of back swing portion, a top of back swing portion, down swing portion, an impact portion, and a follow through portion. For the purpose of analysis of the golf swing, it is necessary to decompose the swing into a sequence of phases. The address portion, takeaway portion, first half of back swing, top of back swing, down swing, impact portion and follow through portion all represent bite-sized portions of the swing that facilitate practical analysis and interpretation.

At least some embodiments further include analyzing the address portion, comprising processing the sensor data to determine whether a lie angle is too shallow, optimal, or too high. This analysis is further disclosed by the flow chart of FIG. 6.

At least some embodiments further include analyzing the takeaway portion, comprising processing the sensor data to determine whether a takeaway direction of the takeaway portion is outward, straight back, or inward. This analysis is further disclosed by the flow chart of FIG. 8.

At least some embodiments further include analyzing the first-half of back swing portion, comprising processing the sensor data to determine whether a backswing plane is vertical, optimal, or flat. This analysis is further disclosed by the flow chart of FIG. 10.

At least some embodiments further include analyzing the top of back swing portion, comprising processing the sensor data to determine whether a backswing length is too short, optimal, or parallel at top of the back swing portion. This analysis is further disclosed by the flow chart of FIG. 14.

At least some embodiments further include analyzing the down swing portion, comprising processing the sensor data to determine whether a downswing plane is vertical, optimal, or flat. This analysis is further disclosed by the flow chart of FIG. 12.

At least some embodiments further include analyzing the impact portion, comprising processing the sensor data to determine whether a release time is too early, optimal, or too late. This analysis is further disclosed by the flow chart of FIG. 16.

At least some embodiments further include analyzing the impact portion, comprising processing the sensor data to determine whether a timing of top speed of the golf swing is reach before impact, at impact or after impact with a golf ball. This analysis is further disclosed by the flow chart of FIG. 18.

At least some embodiments further include analyzing the down swing portion, comprising processing the sensor data to determine whether a downswing acceleration is constant, early or late.

At least some embodiments further include analyzing the down swing portion, comprising processing the sensor data to determine whether a downswing arc relative to an arc of a backswing.

At least some embodiments further include processing the sensor data to determine a sensed wrist rotation comprising determining an orientation of the golf club as the golf club traverses through a backswing and a downswing.

For at least some embodiments, the controller 2430 is operative to sense electrical and mechanical contact of the mechanical switch 2410 due to the sensing apparatus having been subjected to a level of acceleration greater than a minimal threshold amount. For example, motion of a golf club that the sensing apparatus is attached to can cause the mechanical switch 2410 to at least momentarily close due to an electrical and mechanical contact of electrical conductors within the mechanical switch 210.

For at least some embodiments, the controller 2430 senses when the at least momentary closing of the mechanical switch 2410 occurs. When the at least momentary closing of the mechanical switch 2410 is sensed, the controller 2430 controls the electrical power provided to the motion sensors (sensing electronics) 2420. For example, the controller 2430 can provide electrical power to the motion sensors 2420 and to the I/O electronics as provided by a battery 2460.

When a user of the sensing apparatus 2400 is attempting to use or activate the sensing apparatus 2400, the mechanical switch 2410 is tuned to at least momentarily close. That is, the user of the sensing apparatus 2400 subjects the sensing apparatus 2400 to a level of acceleration that causes the mechanical switch 2410 is tuned to at least momentarily close.

As described, the apparatus 2400 includes the mechanical switch 2410. Further, the mechanical switch 2410 includes a switch contact, wherein the switch contact is open when the mechanical switch 2410 is at rest, and at least momentarily closed when the mechanical switch 2410 is subject to at least a threshold level of acceleration. Further, the controller 2430 is operative to activate the apparatus upon detecting that the mechanical switch is at least momentarily closed.

For at least some embodiments, the apparatus 2400 includes an athletic movement sensing device.

For at least some embodiments, the mechanical switch includes a conductive mechanical cantilever or a conductive torsion bar, wherein the conductive cantilever or conductive torsion bar deforms when subjected to acceleration. For at least some embodiments, the conductive cantilever or conductive torsion bar deforms enough to at least momentarily mechanically and electrically contact a conductor of the mechanical switch, thereby at least momentarily closing the mechanical switch when subjected to the threshold level of acceleration. For at least some embodiments, the conductive cantilever or conductive torsion bar is mechanically tuned to deform to at least momentarily mechanically and electrically contact the conductor of the mechanical switch based on a type of athletic movement being sensed by the apparatus.

For at least some embodiments, the switch contact includes a mechanical and electrical contact when the switch contact is at least momentarily closed. For at least some embodiments, the controller senses either the mechanical or the electrical contact, and activates the apparatus. For at least some embodiments, the apparatus 2400 further includes the motion sensing electronics 2420, wherein the controller 2430 activates the motion sensing electronics 2420 after sensing either the mechanical or the electrical contact.

For at least some embodiments, the controller 2430 is further operative to de-activate the apparatus 2400 after sensing a lack of motion of the apparatus 2400 for at least a threshold period of time. For at least some embodiments, the controller 2430 is further operative to de-activate the apparatus 2400 after sensing a specific sequence of motion of the apparatus 2400. For at least some embodiments, the motion or lack of motion is sensed by the motion sensors 2420 of the apparatus 2400. For at least some embodiments, the motion or lack of motion is sensed by the mechanical switch 2410 of the apparatus 2400.

For at least some embodiments, the motion sensing electronics 2420 is operative to sense specific athletic movements after the motion sensing electronics 2420 is activated. For at least some embodiments, the apparatus 2400 is attachable to a golf club, and the motion sensing electronics 2420 is operative to sense a swing of the golf club.

At least some embodiments include a method of analyzing a golf swing. For an embodiment, the method includes sensing motion, by a motion sensing device attached to a golf club, the motion sensing device comprising a controller and one or more motion sensors, accessing, by a controller, sensor data generated based on sensed signals of the one or more motion sensors, performing pattern recognition analysis on the sensor data, comprising identifying and analyzing at least a portion of a golf swing based on the sensed data, wherein the at least one portion of the golf swing includes at least one of an address portion, a takeaway portion, a first-half of back swing portion, a top of back swing portion, down swing portion, an impact portion, and a follow through portion.

Although specific embodiments have been described and illustrated, the embodiments are not to be limited to the specific forms or arrangements of parts so described and illustrated. 

What is claimed:
 1. A golf swing analysis system, comprising: a motion sensing device attached to a golf club, the motion sensing device comprising a controller and one or more motion sensors; a remote processor, wherein a wireless link electronically connects the remote processor and the controller of the motion sensing device; wherein at least one of the controller and the remote processor are operative to: access sensor data generated based on sensed signals of the one or more motion sensors; perform pattern recognition analysis on the sensor data, comprising identifying and analyzing at least a portion of a golf swing based on the sensed data.
 2. The system of claim 1, wherein at least one of the controller and the remote processor are further operative to: perform the identifying and analyzing of the at least a portion of a golf swing based sensed linear axis rotation and sensed angular axis of rotation of the golf club.
 3. The system of claim 2, wherein the sensed linear axis of rotation includes three degrees of freedom and the sensed angular axis of rotation includes three degrees of freedom.
 4. The system of claim 1, wherein the pattern recognition analysis comprises conditional processing, wherein conditions of the processing are dependent upon sensing motion thresholds.
 5. The system of claim 4, wherein the motion thresholds comprise at least one of linear axis of rotation motion thresholds and angular axis of rotation motion thresholds.
 6. The system of claim 1, wherein the at least one portion of the golf swing is identified based on a temporal component, a displacement component and an acceleration component.
 7. The system of claim 1, wherein the at least one portion of the golf swing includes at least one of an address portion, a takeaway portion, a first-half of back swing portion, a top of back swing portion, down swing portion, an impact portion, and a follow through portion.
 8. The system of claim 7, further comprising analyzing the address portion, comprising processing the sensor data to determine whether a lie angle is too shallow, optimal, or too high, comprising sensing an X-axis along a shaft of the golf club, sensing a gravity vector, and computing an angle between the x-axis and the gravity vector.
 9. The system of claim 7, further comprising analyzing the takeaway portion, comprising processing the sensor data to determine whether a takeaway direction of the takeaway portion is outward, straight back, or inward, wherein determining the takeaway direction comprises: sensing accelerometer data and gyroscope data of the sensor data during the takeaway portion, wherein the accelerometer data includes Z-axis motion, wherein the Z-axis motion is perpendicular to a shaft of the golf club and planar to grooves of the golf club, and wherein the gyroscope data includes rotational (β-axis) movement of the golf club that is perpendicular to a shaft of the golf club and planar to grooves of the golf club; determining the takeaway direction by identifying negative or positive directions of the Z-axis motion and negative or positive rotational (β-axis) movement of the golf club.
 10. The system of claim 7, further comprising analyzing the first-half of back swing portion, comprising processing the sensor data to determine whether a backswing plane is vertical, optimal, or flat, wherein analyzing the first-half of the back swing comprises: continuously collecting the sensor data; identifying a condition of no movement for greater than a threshold of time; computing a backplane plane that is a closest match plane for a backswing arc; computing an angle between the backswing plane and a gravity vector of the sensor data; and comparing the angle with a predetermined set of thresholds, wherein the predetermined set of thresholds identify the backswing plane as vertical, optimal, or flat.
 11. The system of claim 7, further comprising analyzing top of back swing portion, comprising processing the sensor data to determine whether a backswing length is too short, optimal, or parallel at top of the back swing portion.
 12. The system of claim 7, further comprising analyzing the downswing portion, comprising processing the sensor data to determine whether a downswing plane is vertical, optimal, or flat, comprising: ascertaining that the golf swing is at a top of a back swing of the golf swing, comprising identifying a momentary pause and a transition of a Y-axis angular rotation from negative to positive, wherein the Y-axis is perpendicular to shaft of the golf club and perpendicular to grooves of the golf club; computing a three-dimensional arc of the downswing; identifying a downswing plane by computing a closest match plane of the three-dimensional arc of the downswing; computing an angle between the downswing plane and a gravity vector; comparing the angle with a predetermined set of thresholds, wherein the predetermined set of thresholds identify the backswing plane as vertical, optimal, or flat.
 13. The system of claim 7, further comprising analyzing the impact portion, comprising processing the sensor data to determine whether a release time is too early, optimal, or too late, wherein determining whether the release time is too early, optimal, or too late comprises: continuously collecting the sensor data; ascertaining the golf club to be at a top of a backswing by identifying a momentary pause of the golf club and identifying a transition of a Y-axis angular rotation from negative to positive, wherein the Y-axis is perpendicular to shaft of the golf club and perpendicular to grooves of the golf club; identifying a double pendulum motion based on a sensed γ-axis angular rotation, wherein the γ-axis angular rotation is perpendicular to shaft of the golf club and parallel to grooves of the golf club; determining an angle between and X-axis of motion and a ground plane, wherein the X-axis is along a shaft of the golf club; and based on the determined angle, identify whether the release time is too early, optimal, or too late.
 14. The system of claim 7, further comprising analyzing the impact portion, comprising processing the sensor data to determine whether a timing of top speed of the golf swing is reach before impact, at impact or after impact with a golf ball, wherein determining whether a timing of top speed of the golf swing is reach before impact, at impact or after impact with a golf ball comprises: continuously collecting the sensor data; ascertaining the golf club to be at a top of a backswing by identifying a momentary pause of the golf club and identifying a transition of a Y-axis angular rotation from negative to positive, wherein the Y-axis is perpendicular to shaft of the golf club and perpendicular to grooves of the golf club; identifying a characteristic motion signature pattern to indicate impact between the golf club and a golf ball; after identifying the characteristic motion signature pattern to indicate impact between the golf club and a golf ball, determining whether a sample of an γ-axis angular speed of the sensor data is faster, equal or slower than a prior sample of the γ-axis angular speed of the sensor data, wherein the γ-axis angular speed is perpendicular to shaft of the golf club and parallel to grooves of the golf club; and determining whether the timing of top speed of the golf swing is reach before impact, at impact or after impact with the golf ball based on whether sample of the γ-axis angular speed of the sensor data is faster, equal or slower than the prior sample of the γ-axis angular speed of the sensor data.
 15. The system of claim 7, further comprising analyzing the down swing portion, comprising processing the sensor data to determine whether a downswing acceleration is constant, early or late, wherein determining whether a downswing acceleration is constant, early or late comprises: continuously collecting the sensor data; ascertaining the golf club to be at a top of a backswing by identifying a momentary pause of the golf club and identifying a transition of a Y-axis angular rotation from negative to positive, wherein the Y-axis is perpendicular to shaft of the golf club and perpendicular to grooves of the golf club; collecting Y-axis angular acceleration and X-axis linear acceleration in the early stage of the downswing, wherein the Y-axis angular acceleration is perpendicular to shaft of the golf club and perpendicular to grooves of the golf club and the X-axis linear acceleration is parallel to a shaft of the golf club; collecting Y-axis angular acceleration and X-axis linear acceleration in the late stage of the downswing; and determining the downswing acceleration to be constant, early or late based on whether the Y-axis angular acceleration and X-axis linear acceleration in the early stage of the downswing exceed, is equal to, or less than the Y-axis angular acceleration and X-axis linear acceleration in the late stage of the downswing.
 16. The system of claim 7, further comprising analyzing the down swing portion, comprising processing the sensor data to determine a downswing arc relative to a backswing arc, wherein determining the downswing arc relative to the backswing arc comprises: continuously collecting the sensor data; ascertaining the golf club to be at a top of a backswing by identifying a momentary pause of the golf club and identifying a transition of a Y-axis angular rotation from negative to positive, wherein the Y-axis is perpendicular to shaft of the golf club and perpendicular to grooves of the golf club; using sensor data samples from the linear axes and the angular rotation axes to plot the backswing and downswing in 3-dimensional space; recording relative positions of the downswing arc and backswing arc; and identifying the downswing arc relative to the backswing arc as inside, same, or outside based on the relative positions of the downswing arc and backswing arc.
 17. The system of claim 7, further processing the sensor data to determine a sensed wrist rotation comprising determining an orientation of the golf club as the golf club traverses through a backswing and a downswing, comprising: continuously collecting the sensor data; identifying a condition of no movement for greater than a threshold of time; identifying a condition in which an Y-axis is moving in the negative direction combined with an γ-axis angular motion commencing, thereby indicating a start of the backswing, wherein the Y-axis is perpendicular to shaft of the golf club and perpendicular to grooves of the golf club and the γ-axis angular motion is perpendicular to shaft of the golf club and parallel to grooves of the golf club; after start of the backswing, identifying a condition in which a γ-axis rotates 90 degrees; after the condition in which a γ-axis rotates 90 degrees, computing an angle between a Z-axis and a ground plane, wherein the Z-axis is perpendicular to shaft of the golf club and planar to grooves of the golf club; compute rotation in an α-axis, wherein the α-axis is planar to the shaft of the golf club; determining the orientation of the golf club as the golf club traverses through a backswing and a downswing as under-rotation of the golf club, optimal rotation of the golf club, over-rotation of the golf club based on whether the angle is less than 90 degrees, approximately equal to 90 degrees, or greater than 90 degrees.
 18. A method of analyzing a golf swing, comprising: sensing motion, by a motion sensing device attached to a golf club, the motion sensing device comprising a controller and one or more motion sensors; accessing, by a controller, sensor data generated based on sensed signals of the one or more motion sensors; performing pattern recognition analysis on the sensor data, comprising identifying and analyzing at least a portion of a golf swing based on the sensed data, wherein the at least one portion of the golf swing includes at least one of an address portion, a takeaway portion, a first-half of back swing portion, a top of back swing portion, down swing portion, an impact portion, and a follow through portion. 